GROWTH AND YIELD ATTRIBUTES OF WHEAT AT DIFFERENT SEED RATES

Optimum seeding rate is one of the most important production factors for higher grain yield as well as for quality crop. Indiscriminate use of seeding rates not only increases production costs but usually decrease wheat grain yield. Field trials were conducted at Sindh Agriculture University Tandojam, Pakistan during 2007-08 to evaluate the effect of different seed rates (125, 150, 175 and 200 kg ha -1 ) on growth, yield and nutrient uptake of wheat varieties (TD -1 , TJ-83 and Mehran-89). Seed rates significantly affected all the plant traits. Crop sown at low seed rate of 125 kg ha -1 had better growth, yield, nutrient uptake and low lodging tendency. Maximum tillers, spike length, grains spike -1 , grain weight spike -1 , seed index, biological yield, grain yield, harvest index, dry matter, crop growth rate and low lodging were found in TD -1 sown at 125 kg ha -1 seed rate. However, higher seed rates (200 kg ha -1 ) resulted in delayed maturity, greater internode length and higher lodging in Mehran-89. However, TJ-83 was inefficient and recorded minimum values of all the growth, yield, nutrient uptake and traits. It was concluded that wheat variety TD -1 could be sown at optimum seed rate of 125 -1 50 kg ha -1 for better growth, yield, nutrient uptake